Two Chinese police cars damaged by homemade bombs in Tibet protest

KANGDING, China - Two police cars were damaged by homemade bombs in western Qinghai province, a state news agency reported Monday, as the government widened its security lockdown and sealed off a restive Tibetan region to foreigners ahead of two sensitive anniversaries.

The official Xinhua News Agency did not give a reason for the blasts, which took place 2 a.m. Monday after police clashed with several people while trying to check a lumber truck in the province.

Police have increased checks on vehicles in places with minority Tibetan populations, including Qinghai, ahead of Tuesday's 50th anniversary of a failed revolt that sent the Dalai Lama into exile.

Saturday is the one-year anniversary of riots against Chinese rule in Tibet's regional capital of Lhasa that were triggered after police blocked monks trying to commemorate the 1959 uprising.

Calls to police stations in Qinghai rang unanswered.

No fatalities were reported, and it was not known if the blasts were connected with the tensions over Tibet, but the move to seal off a region in neighboring Sichuan was the latest in a series of increasingly strict measures taken by Beijing to quash any dissent this week and prevent a repeat of violent demonstrations against Chinese rule.

In recent weeks, convoys of armored vehicles and military trucks have crisscrossed the mountain roads of Tibet and other parts of China's volatile far west, which saw pockets of unrest after the Lhasa riots. Police and troops have amassed in Tibetan communities, where chains of checkpoints have been set up.

In Sichuan province's Ganzi prefecture, where some of the most violent protests took place last year, officials said they received an emergency notice Monday from the provincial government that Ganzi was now shut off to all foreigners. Similar blocks have been issued in Tibetan areas in neighboring Gansu and Qinghai provinces.

"There is a special situation and we hope you can leave as soon as possible," Zhang Lijuan of the Ganzi prefecture foreign affairs office told Associated Press reporters in Kangding, where the Ganzi prefecture government is based. "Normally, this is an open place and we would welcome you. But because of this special situation, it's not convenient."

Li said she could not reveal the reason for the closure but said Kangding was also temporarily sealed off after last year's demonstrations. She said she did not know when the area would be reopened.

The streets of Kangding were busy on Monday, with many residents shopping and working as normal. Police cordoned off traffic around the area in front of the town's main square, where riot police and machine gun-toting soldiers now regularly march past.

Ganzi prefecture, known for its strong sense of Tibetan identity and nationalism, is home to the Tongkor monastery, where rights groups say skirmishes broke out last April when Chinese officials demanded that monks denounce their spiritual leader, the Dalai Lama.

In Beijing, a top police official said China has tightened its border control in Tibet for fear of potential disruptions by supporters of the Dalai Lama, according to the official Xinhua News Agency.